High intensity, gas discharge luminaires, which are hereinafter referred to as HID luminaires, are commonly installed at high locations at commercial or industrial facilities such as on the ceiling of a warehouse or plant, or on light poles in a parking lot or stadium. HID luminaires can include, but are not limited to, metal halide or MH lamps, and high pressure sodium or HPS lamps. HID luminaires use pulses from a high voltage source such as a starting circuit to ignite the lamp.
In many applications, the HID luminaires can be elevated on the order of thirty feet or more above the floor or ground at a commercial or industrial facility. The elevation of the luminaires makes repair of malfunctioning luminaires inconvenient and time consuming since service personnel must ascend to considerable heights in order to gain access to the luminaires, assess the problem and then repair or replace components of the luminaire. The malfunctioning of an HID luminaire can be attributed to any of a number of problems such as a defective ballast or ballast capacitor, a defective lamp, loss of supply voltage or defective lamp starting circuit, which is hereinafter referred to as an ignitor.
A number of devices exist to facilitate the assessment of a malfunctioning luminaire. For example, U.S. Pat. No. 4,318,031, to Lonseth et al, discloses a visual monitoring device having two indicator lights for indicating the operational conditions of a lamp, a ballast and a starter circuit, as shown in FIG. 1. The first indicator light is provided across the lamp and indicates whether the lamp or the ballast have failed. The second indicator light is driven by a voltage divider circuit comprising resistors connected to the output of the ballast. The starter circuit is connected to a power source, to the ballast, and to the junction between the lamp and a lead-type ballast capacitor, and is configured to provide the lamp with pulses. The pulses are divided by the voltage divider circuit and the resulting pulses are provided to a diode. The resulting pulses are of sufficient voltage to allow the conduction of the diode and storage by a capacitor. Under normal operating conditions of the starter circuit, pulses are stored during each cycle of a 60 Hertz line current. The indicator light operates when thirty pulses are stored or twice a second.
If the indicator light does not blink and the lamp is off, then the starting circuit is malfunctioning. A service person must then interrupt the supply of power to the luminaire and ascend a ladder or use other means to reach the elevated luminaire in order to remove the luminaire from the ceiling or other surface to which it is mounted. Secondly, the luminaire housing must be opened and circuit connections disconnected to remove the malfunctioning starter circuit and replace it with a new starter circuit. As stated previously, these types of repairs are costly in terms of man-hours required to perform the above operations. Further, such repair operations can potentially expose a service person to electric shock if the luminaire housing is opened before line power to the luminaire is terminated for repair purposes. Thus, a need exists for a luminaire which has an ignitor or starting circuit that is connected to the outside of the luminaire housing, as well as an ignitor indicator. The starting circuit can therefore be removed and replaced with relative ease and without having to interrupt power to the luminaire or risk exposure to electric shock.